The present invention relates to a semiconductor laser device and a method of manufacturing the same.
A perspective view of a conventional semiconductor laser device is shown in FIG. 5. An n-type GaAs substrate 1 is formed on a n side electrode 10 made of an AuGe/Au alloy. Sequentially formed in order on the surface of the n-type GaAs substrate 1 are formed an n-type InGaAlP clad layer 2, InGaP active layer 3, p-type InGaAlP clad layer 4, p-type InGaP layer 5, n-type GaAs current block layer 6, and p-type GaAs cap layer 7. A p side electrod 11 made of AuZn/Au alloy is formed on the surface of the p-type GaAs cap layer 7. This device is formed to have a double hetero structure in order to enhance light emission. When current flows upon the application of voltage across the p and n side electrodes 11 and 10, a laser beam is radiated from a pair of side faces A which are crystal cleavage faces.
The semiconductor laser device constructed as above is fixedly mounted on a stem 13 made of copper (Cu) with gold (Au) being plated. The surface of the p side electrode 11 is fixedly attached to the stem 13 using a soldering agent 12 made of a low melting point metal such as indium (In), and a lead (Pb)-tin (Sn) alloy.
A conventional semiconductor device however has the problem that soldering agent 12 creeps up a pair of side faces B perpendicular to the crystal cleavage faces A, resulting in a short-circuited device. FIG. 7 illustrates this creep-up phenomenon of soldering agent 12. The conductive soldering agent 12 bonding together the stem 13 and the p side electrode 11 creeps up to the p-type InGaAlP clad layer 4, short-circuiting the clad layer 4 to the p side electrode 11.
For semiconductor laser devices in particular, a red semiconductor laser device using InGaAlP of large specific heat, faults of semiconductor laser devices caused by short-circuits have occurred heretofore many times, lowering manufacturing yield